B2 Audio IS15 D4 v3

15″ subwoofer · dual 4 Ω · 750 W RMS

Fs 33 HzQts 0.77Vas 2.26 ft³Xmax 0.71″

Recommended box

For a sedan, one sub, 750 W. It’s the same math as the designer’s step-by-step mode, where you can fit the box to your space, vehicle and amp and get plans, a cut sheet and DXF.

Sealed

Net volume2.83 ft³ (80 L)
Qtc1.04
Fc44 Hz
F3 (−3 dB, no cabin gain)36 Hz
Example box (outside)31 1/2″ × 17 11/16″ × 12″
Open sealed box in designer

Ported

Net volume4.80 ft³ (136 L)
Tuning (Fb)31 Hz
Portslot 2 3/4 × 16 5/16″, 20 1/2″ long
Port velocity at 750 W65 ft/s
F3 (−3 dB, no cabin gain)26 Hz
Example box (outside)31 1/2″ × 17 11/16″ × 21 3/16″
Open ported box in designer
203040506080100150200667278849096HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs33 Hz
Qts0.77
Qes0.86
Qms7.6
Vas2.26 ft³
Re (one coil)3.3 Ω
Sd≈ 124 in²
Xmax0.71″
EBP38 — suits sealed calc.
Sensitivity, 1 W / 1 m86.3 dB calc.

General

Size15″
Voice coilsdual 4 Ω
RMS power750 W

Mounting dimensions

Ø15 3/8″cutout ≈ Ø13 13/16″mounting depth ≈ 7 1/16″magnet Ø≈ 9″
Cutout diameter≈ 13 13/16″
Mounting depth≈ 7 1/16″
Overall diameter15 3/8″

“≈” means the value isn’t in the spec sheet and a typical value for the size is used; “calc.” means it’s calculated from the published parameters. Check the manufacturer’s spec sheet before you build.

Data sources

Other B2 Audio 15″ models